My company not only uses Marketo for ourselves, but we also use the software for other companies by having them purchase other instances through our platform. There is only one part in the entire process that frustrates us and our clients, which is the IT setup. Can someone give me a clear cut description of how they do this step? An example issue we've ran into is a client in the financial industry not wanting to perform step 2, which is the "Whitelist Marketo IPs" step. We know we can purchase the branded return path option, but we're seeing if we can take another route before. We aren't the most tech savy around here, but would love to learn more on the IT setup.

I definitely do not support whitelisting all emails from Marketo IPs, or even from a single dedicated instance IP.

In the first case, you'll not only obscure deliverability issues (you'll get your samples, your leads might get nothing) but will also end up getting unwanted email from other Marketo customers.

In the second case, while you won't be allowing 3rd-party spam, you will still be obscuring deliverability problems. Remember, your spam filter is the "first responder": don't deprive yourself of this critical diagnostic tool.

If you want to make sure that email can be proofed regardless of its real-world deliverability, create a single mailbox that still scans and tags spamlike behavior (w/failed spam tests noted in SMTP headers) but which doesn't block mail outright.

“We have as per the configuration document requested the CNAMES and SPF records be added for the web addresses/emails requested. However, we have concerns regarding the addition of a whitelisting of mktomail.com and their respective IP addresses. Upon quick glance we have received nearly 4000 emails from this domain just in 2018. Much of this is spam and while we don’t explicitly blacklist this domain it is one of our top spam domains that gets blocked regularly. Hard whitelisting these IPs would automatically send all of this mail into our inboxes which is something we really don’t want to do. Would it be possible to get a specific email address to whitelist (eg. sfsb@mktomail.com) as opposed to the whole domain? Is there any other path or solution we can look at to make this work for us?”

Above is what our client sent us. Can you please read this and educate me on what you'd do here?

Is that as simple as them whitelisting a created branding domain for them?

Below is another email we received from them if it makes things clearer.

"Per the list of IPs they gave we receive the following amount of spam/junk emails from each IP since January 1st 2018:

199.15.213.50: 105

199.15.213.51: 41

199.15.213.52: 19

199.15.213.53: 20

192.28.152.139: 58

192.28.152.140: 42

192.28.152.141: 76

192.28.152.142: 20

192.28.150.226: 31

192.28.150.227: 28

192.28.150.228: 24

192.28.150.229: 43

199.15.213.62: 1

199.15.213.63: 0

For a total of 508 or a little over 100 spam emails a month. This is significantly less than the original amount that we were concerned about but it’s still a lot and it’s also assuming that their volume doesn’t increase among these IP addresses over time (as spam bots tend to do). Is there any way we can get a definitive/static email address to whitelist or help us filter through this mail?"